The article focuses on the causes of refractoriness of sulfide ore stock with superdispersed gold inclusions. In order to increase gold recovery, a hypothesis about effective (peroxide) preparation of refractory raw materials in the process of leaching has been described. The author focuses on theoretical justification of the physicalchemical model and the two-stage mechanism of oxidation (photoelectrochemical and bacterial) of material using microorganisms Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. A scheme of two-staged (physicochemical and bacterial) oxidation was developed. It is based on photoelectrochemical effects for the leaching of gold from refractory materials. It is shown that photoelectrochemical pre-oxidation makes it possible to increase development of the mineral matrix with its further bacterial oxidation. It also helps to increase the efficiency of invisible gold extraction from sulfide ores. Laboratory tests have been performed on the combined oxidation scheme on electroactivation carbon-in-leach of invisible gold from the Kokpatas deposit’s sulfide ores. The authors present the results of the laboratory tests of the activation methods for impacting upon the refractory ores before metal leaching, which prove the efficiency of such non-traditional methods for developing mineral matrix. Gold extraction using the combined technology of sulfide and arsenopyrite oxidation increases by 18%.

This study provides the results of analysis of mine belt conveyor downtime and considers the relevance of monitoring their technical condition. The monitoring results of VFD conveyor gear units regarding lube oil and vibration parameters are presented.

Large electricity consumers – mining companies – along with active power consumed reactive power, creating network flows. The issues of compensation of reactive power and rational placing of the compensating devices are becoming highly relevant in the light of energy saving policies. Compensation is particularly important when optimization of voltage and power consumption in order to reduce active losses and improve power quality. Effective action for reduction of losses in electric networks is installation of devices of reactive power compensation (RPC). In the analysis of methods of calculation of optimal power compensating devices, and location were taken into account the specificity of mining enterprises, namely the separation of electrical networks underground and surface. The objective function formulated on the basis of annual reduced costs and identified system limitation, when considered in the objective function. The analysis of the objective function showed that it separaely and the problem can be solved by methods of discrete programming.

Moisture in frozen rocks and soils is presented in the General case in the form of two components – ice and unfrozen water. To quantify the moisture content in these rocks were previously proposed two measures, named total and total moisture. The paper shows that such names incorrectly reflect the essence of these indicators. Actually it is the total mass humidity and moisture content. For a more complete and accurate assessment of the influence of moisture on physical properties of frozen rocks is proposed to use the total volume and absolute humidity and moisture content. Identified the relationship between all considered in the totals of moisture in frozen rocks.

In the formation of the well under the influence of an axial load and speed core drilling shell is curved, with its lower bottomhole part consists of elements of different stiffness: a set of core and drill pipe. To determine the length of the half-wave in this part of the technological tools used energy method, according to which the whole work of external forces on the length of said potential energy goes into twisted drill. The solution of the corresponding equation is possible to obtain a formula for determining the length of the halfwave of the bottom-hole shell. The resulting relationship is different from the well-known formula B. I. Vozdvizhenskogo, MG Vasilyeva that it additionally takes into account the ratio of the core set, and half-wave ratio of moments of inertia and the core set of drill pipes and the mass ratio of coring and drilling labor per unit length. To reduce the curvature of the wells is recommended to install in the "crests" half-waves of the bottomhole shell ribs.

Vietnam has potential reserves of titanium placers, located mainly along the coast of the Middle spreading across provinces from Thanh Hoa to Ba Ria – Vung Tau. Mining titanium placers deposits has gained considerable profit for localities and the country as a whole, but it has also given rise to significant environmental issues. The paper introduces the potential of titanium placers in Vietnam, current mining status and environmental issues faced, and then proposes a number of strategic orientations for sustainable development of the future titanium industry of Vietnam. These orientations are completely feasible with regard to the titanium placer mines of Vietnam in order to consider and apply effectively for suitable conditions. They also represent a useful reference for similar titanium placer mines in the world.

Exploitation of landslide-prone escarpments of middle safety factor, or in a state of limiting equilibrium can lead to a crash when changing the seismic and hydro-geological situation. In this connection it is necessary to develop recommendations for the deployment of a network of information collection points hydrogeomechanical c monitoring high density for rapid notification of reaching the critical water level and management decisions to strengthen the slope.

This article presents a study on the application of remote sensing techniques to detect clay minerals, iron oxide and ferrous minerals using LANDSAT 7 ETM+ multispectral images. We used band ratio method to determine areas that are rich and poor in mineral composite content. The results obtained in this study can be used to create a distribution map of clay mineral and iron oxide, and to facilitate mineral mining and exploration.

The article describes the escalator tunnel construction using tunnel boring machines in St. Petersburg. To reduce the harmful effects of underground construction on the Earth's surface in the mouth of the tunnel technology is used jet grouting rock mass. Based on the analysis of field data of the earth surface subsidence and rock strata proved the effectiveness of the jet grouting technology. Subsidence of the surface and within the grouting area, are approximately null. The fact that the development of subsidence occurs mainly outside the zone of jet grouting soil is shown. A method of reducing subsidence by grouting additional unstable rocks in the massif, which will reduce the harmful effects of underground construction for an massif and the earth's surface, is offered. To assess the efficiency of the proposed method, a numerical modeling based on the finite element method is carried out. According to the modeling results it is revealed that the proposed method will reduce the subsidence at the surface by 2-3 times.

Russian industry embarking on an innovative development path reflects world trends of international cooperation among higher education institutions dealing with engineering staff training and integration of higher technical education. Russia’s joining the Bologna Process requires that higher schools prepare graduates, on the one hand, for an immediate start of professional activity at enterprises and, on the other, to ensure their mobility on the global
labor market. At the same time, Russian higher education institutions should be capable of training engineers from foreign countries, attaining the international level of skills training. The training of mining engineers in Russian technical universities cannot stand apart from the international integration of the educational process. The generality of technological, production and administrative processes of the mining industry in different countries makes the international integration of the higher education of mining engineers in Russia especially topical. However, the low standing of Russian technical universities in the world ratings, the limited acknowledgment of Russian diplomas abroad, insufficient study motivation of students and poor foreign language skills all serve to constrain the process of international integration of Russian higher mining education. The response to the challenges placed by globalization of the higher education system and the compelling need for the international expansion of Russian higher schools should become innovative, interactive and language determinants of this process. They represent the conditions that determine the prospects for integration of mining engineers’ higher training in the international economic community. The given determinants should be implemented at the level of specific higher education establishments by using innovative pedagogical technologies, such as binary lectures, role-plays, brainstorming, case study, and project training in the educational process.